A TEAM of researchers from Pune, as a part of an international collaborative study, has devised a biofilm possessing anti-bacterial and disease fighting capacity against aedes aegypti — a vector that causes zika, dengue and chikungunya diseases among humans.

According to the team, a film, coated with silver and gold nanoparticles and obtained from protein of mulberry silk, was able to completely kill the larva of aedes aegypti. The scientists used this film, which was coated with nanoparticles synthesised from mulberry grown locally in and around Junnar, located about 80 kms from Pune. Silk being a fibre produced by the silkworms consists of two proteins — fibroin and sericin. This film was later subjected to the growth of larva and tested over a period of eight days.

Dinesh Amalnerkar from Hanyang University and former executive director of the Centre for Electronics and Materials Energy Technology (C-MET), said, “The resultant nanosilver and nanogold-based fibroin solution and films were tested for anti-bacterial activity against various bacteria E coli, S aureus, K pneumoniae, P Aeruginosa and antifungal activity against A fumigates. Nanosilver-based solution exhibited an effective anti-microbial action against all these microbes as compared to nanogold solution. Additionally, nearly 100 per cent mortality of aedes aegypti mosquito larva in the water-insoluble films was obtained, while the films of gold-based nanocomposite revealed 86-98 per cent mortality.”

According to statistics maintained by the National Vector Borne Disease Control Programme, there were a total of 5,01,31 cases of dengue and 1,87,829 cases of chikungunya in the country during 2013 – 2017 (until December 17).
The study, which was recently published in Scientific Reports (Nature Publishing Group ), revealed that the bio-nanocomposite material ability could restrict the growth of aedes aegypti , the other infections like flavivirus, malaria, yellow fever, filariasis, schistosomiasis, Japanese encephalitis can automatically be curbed and effectively controlled, highlighted Amalnerkar.

Alongside preventing the mosquito breeding, co-researcher R D Chaudhari, head of the Zoology Research Centre at Shri Shiv Chhatrapati College in Junnar, is of the opinion that farmers can hugely benefit from the sale of mulberry silk. The silk is mainly grown in Karnataka, Andhra Pradesh, West Bengal, Tamil Nadu and Jammu and Kashmir, which account for 92 per cent of country’s total mulberry raw silk production.

Chaudhari said, “If we can tap this abundant natural resource, which is available in the form of silks obtained from mulberry tree, and tussar silk. This can potentially become an additional income source for farmers, given that mulberry plant is having a life span of 12 to 15 years.”